Browsing by Author "Licina, Marina M. (54380426100)"

Stroke prevention in atrial fibrillation (AF) has been challenging over decades, mostly due to a number of difficulties associated with oral vitamin K antagonists (VKAs), which have been the most effective stroke prevention treatment for a long time. The oral direct thrombin inhibitors (e.g., dabigatran) and oral direct inhibitors of factor Xa (e.g., rivaroxaban, apixaban) have emerged recently as an alternative to VKAs for stroke prevention in AF. These drugs act rapidly, and have a predictable and stable dose-related anticoagulant effect with a few clinically relevant drug-drug interactions. The novel oral anticoagulants are used in fixed doses with no need for regular laboratory monitoring of anticoagulation intensity. However, each of these drugs has distinct pharmacological properties that could influence optimal use in clinical practice. The following phase 3 randomized trials with novel oral anticoagulants versus warfarin for stroke prevention in AF have been completed: the Randomized Evaluation of Long-term Anticoagulant therapy (RE-LY) trial with dabigatran, the Rivaroxaban Once daily oral direct Factor Xa inhibition Compared with vitamin K antagonism for prevention of stroke and Embolism Trial in Atrial Fibrillation (ROCKET-AF) trial with rivaroxaban, and the Apixaban for Reduction of Stroke and Other Thromboembolism Events in Atrial Fibrillation (ARISTOTLE) trial with apixaban. Moreover, the Apixaban Versus Acetylsalicylic Acid to prevent Strokes (AVERROES) trial included patients with AF who have failed or were unsuitable Stroke prevention in atrial fibrillation (AF) has been challenging over decades, mostly due to a number of difficulties associated with oral vitamin K antagonists (VKAs), which have been the most effective stroke prevention treatment for a long time. The oral direct thrombin inhibitors (e.g., dabigatran) and oral direct inhibitors of factor Xa (e.g., rivaroxaban, apixaban) have emerged recently as an alternative to VKAs for stroke prevention in AF. These drugs act rapidly, and have a predictable and stable dose-related anticoagulant effect with a few clinically relevant drug-drug interactions. The novel oral anticoagulants are used in fixed doses with no need for regular laboratory monitoring of anticoagulation intensity. However, each of these drugs has distinct pharmacological properties that could influence optimal use in clinical practice. The following phase 3 randomized trials with novel oral anticoagulants versus warfarin for stroke prevention in AF have been completed: the Randomized Evaluation of Long-term Anticoagulant therapy (RE-LY) trial with dabigatran, the Rivaroxaban Once daily oral direct Factor Xa inhibition Compared with vitamin K antagonism for prevention of stroke and Embolism Trial in Atrial Fibrillation (ROCKET-AF) trial with rivaroxaban, and the Apixaban for Reduction of Stroke and Other Thromboembolism Events in Atrial Fibrillation (ARISTOTLE) trial with apixaban. Moreover, the Apixaban Versus Acetylsalicylic Acid to prevent Strokes (AVERROES) trial included patients with AF who have failed or were unsuitable. © Springer Healthcare 2012.

Atrial fibrillation (AF) confers a significant risk of ischemic stroke, and oral anticoagulation is the most effective therapy for thromboprophylaxis in AF. Until recently, vitamin K antagonists (VKAs) were the only available oral anticoagulants. However, numerous disadvantages of VKAs and anticipated bleeding risk with treatment have resulted in their substantial underutilization in clinical practice. Recently, the two other classes of oral anticoagulants - direct thrombin inhibitors (e.g., dabigatran) and direct factor Xa inhibitors (e.g., rivaroxaban and apixaban) - have emerged as a viable alternative to VKAs for stroke prevention in AF. In addition, efforts have been made to facilitate the optimal prevention of AF-related stroke by improvement of both stroke and bleeding risk assessment. In this review, we summarize the recent advances and discuss the contemporary practical aspects of stroke prevention in patients with nonvalvular AF. © 2013 Future Medicine Ltd.

Background-The CHA 2DS 2-VASc (Congestive heart failure, Hypertension, Age ≥75 years, Diabetes mellitus, previous Stroke/transient ischemic attack [TIA], Vascular disease, Age 65-74 years, and Sex category [female gender]) schema recently has been introduced to complement the CHADS 2 (Congestive heart failure, Hypertension, Age ≥75 years, Diabetes mellitus, and previous stroke or TIA) score and improve the identification of atrial fibrillation (AF) patients at "truly low risk" for thromboembolism. We tested the predictive ability of the CHA 2DS 2-VASc, CHADS 2, and van Walraven risk stratification schemes in a cohort of "lone" AF patients with a 12-year follow-up. Methods and Results-We conducted a registry-based, observational cohort study of 345 patients initially diagnosed with "lone" AF between 1992 and 2007. At baseline, all patients had the CHADS 2 and van Walraven scores of 0, and 262 (75.9%) had a CHA 2DS 2-VASc score of 0. During follow-up (or within a year prior to stroke), 228 (66.1%), 234 (67.8%), and 150 patients (43.5%) retained the CHADS 2, van Walraven, and CHA 2DS 2-VASc scores of 0, respectively. The overall rate of ischemic stroke was 0.19 (95% CI: 0.18-0.20) per 100 patient years. In the multivariable analysis, only the CHA 2DS 2-VASc score of 0 was significantly related to the absence of stroke (odds ratio 5.1, 95% CI: 1.5-16.8, P=0.008). Only the CHA 2DS 2-VASc score had a significant prediction ability (c-statistic 0.72 [0.61- 0.84], P<0.031). Conclusions-The CHA 2DS 2-VASc score reliably identified the "lone" AF patients who were at "truly low risk" for thromboembolism, and was the only tested risk stratification scheme with a significant predictive ability for thromboembolism among lone AF patients. © 2012 American Heart Association, Inc.